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Create a 140-character tweet summarizing this article.

Additional Context:
WASHINGTON (CNN) -- A wide-open presidential race and a willingness by candidates, interest groups, unions and corporations to buy TV time will lead to historic spending for political and issue-advocacy advertising in the 2008 election cycle, an analysis shows.

Answer:
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In the 2008 election cycle, TV advertising spending is estimated to reach a record high of $3 billion, due to a wide-open presidential race and increased advertising purchases from candidates, interest groups and corporations. #Election2020 #CampaignAdvertising